Archive for the ‘environment’ Category

One of the primary uses of petroleum is as fuel. As the average carbon dioxide levels have already gone above 400 ppm and global warming is taking place, there have been many calls to reduce the usage of petroleum by substituting it with renewable energy. Biofuels stand very distinct among all other renewables because they could be easily used as a drop in replacement for petroleum based fuels.

Petroleum usage

Around 84 percent of the distillates are used as fuels including diesel, gasoline(petrol), kerosene, LPG etc. Considering the oil usage at 94 million barrels per day, this amounts to 4585 billion litres per year.

Biofuel yield

Different biofuel crops have different yields. Typical values are given below.
Biofuel Production L/Ha

Land Requirement to replace the entire petroleum based fuel

Considering the above yield and the amount of petroleum used as fuel, total land usage of different crops to replace the entire petroleum based fuel could be calculated. For comparison two forms of other data is also provided. 1) Total arable and agricultural land available. 2) Land area of some of the larger countries in the world.
Biofuel Production L/Ha

Could Brazil increase the ethanol production 100 times utilizing the entire area of Brazil itself? Otherwise could the entire Sahara Desert or the United States be used for producing palmoil based biodiesel? Could any of these options be possible without touching the remaining tropical rainforests in the world?

As far as land usage is concerned, algae is the only source with a potential to replace the entire petroleum usage. But it is still a reasearch topic for many years, far away from being commerically available.

Read Full Post »

Ships of the desert grazing near deserted ships in Aral Sea desert

Baikonur Cosmodrome, Kazakhstan – First ever window to space. Beginning of the space age was one of the greatest achievements of mankind since the dawn of civilization. Many space scientists, explorers and researchers had gone through the arid steppes of this small Central Asian town. That list includes Sputnik scientists, Yuri Gagarin and many of the International Space Station travelers.

Double Humped Wild Bactrian Camels grazing near abandoned ships in Aral Sea desert

Just 250 km north west of Baikonur lies another small town, supposed to be on the banks of Aral Sea, named Aralsk. Aral Sea was the 4th largest lake by area and 12th largest lake by volume until 1960. It had an area of 68000 square kilometers and a volume of 1100 cubic kilometers. The lake had one third salinity of sea water at around 10g/L. It was fed by two of the largest river ecosystems of Central Asia namely Amu Darya and Syr Darya. Historically known as Oxus and Jaxtares, these two rivers were very famous throughout the Achaemenid Persian, Greek and Arab periods. Amu Darya and Syr Darya have a mean discharge of 97.4 cubic kilometers and 37 cubic kilometers respectively. Source of their water is from the glaciers of Pamir and Tian Shan mountains. Rain water could not contribute much as these steppes are extremely arid with a rainfall of around 30 cm / 12 inches. Temperature could go anywhere between -45 Degree Celsius to 45 Degree Celsius depending upon seasons.

Aral Sea is shared between both Kazakhstan and Uzbekistan. Until around 1960 two towns flourished on the banks of Aral Sea, Aralsk on the north east in Kazakhstan and Muynak on the south west in Uzbekistan. Both were important fishing towns with harbors and processing industry. Uzbekistan used to get around 60% of their fish, that is 25000 tonnes of fish from Aral Sea itself

Things started changing around 1955-1960 when Soviet Union started to improve their agriculture output. Many dams and canals were built to divert large amount of water for irrigation. This reduced the amount of water reaching Aral Sea drastically and Aral Sea started getting dried up very fast. Currently Aral sea got split up into 4 lakes including North Aral Sea and South Aral Sea with a total area of around 6800 square kilometers which is only 10% of its original size. Lake salinity got increased to around 100g/L destroying all fish in the lake.

Aral Sea: Map vs. Satellite image

Cotton Production:

Cotton production also took off like the Soviet space program during 1960s. Uzbekistan’s production increases from 300000 MT in 1950 to around 3 Million MT in mid 1980s. Most of the the cotton was cultivated as a monoculture without crop rotation. This required huge amount of pesticides and chemical fertilizers. Lots of pesticides and fertilizers reached Aral Sea due to run off. Cotton requires large amount of water and virtually all of this water is sourced from Amu Darya and Syr Darya.

Per Capital Water Usage:

Central Asian countries of Turkmenistan, Kazakhstan and Uzbekistan have the highest per capital water usages. Most of the water is sourced from Amu Darya and Syr Darya and used for irrigating cotton plantations.

Per Capital Water Usage of Countries

Environmental issues:

There are many environmental problems associated with aral sea crisis. Farming without crop rotation depletes soil of nutrients and increases the salt content in the soil. Cotton production of Uzbekistan went down by half from its peak values during 1980s.

Aralkum is the new desert appeared on the dried up seabed of Aral Sea. It is estimated that Aralkum has an area of around 55000 square kilometers. It is a mixture of sand, salt, run-off pesticides and fertilizers. About 200000 Tonnes of salt and sand are carried by the wind from Aral Sea everyday and dumped withing 300 km radius. This pollution is decreasing available agricultural area due to salt content. This increases respiratory problems in people. There have been instances of this pollution reaching as far as the Arctic north of Russia.

A view from Muynak Port in Uzbekistan: abandoned ships

Difference approaches of Kazakhstan and Uzbekistan

Out of all countries in the Amu Darya and Syr Darya region, Kazakhstan is taking some effort to restore North Aral Sea. They have created Kok Aral Dam in 2005 with the help of World Bank spending $64 Million. This dam traps water from Syr Darya and redirect it back to North Aral Sea. Due to this water levels in North Aral Sea is increasing and its salinity is going down. Aralsk used to be around 100 km away from North Aral Sea in 2005, but after the construction of the Dam it is around 6 km away. Also area of North Aral Sea got increased from around 2550 square km in 2003 to 3300 square km in 2008.

Cranes near dried up Aral Sea in Aralsk port, Kazakhstan

On the other side, Uzbekistan has not done anything practically to restore Aral Sea. Some figures says that around 50000 people of Karakalpakstan region of Uzbekistan have already left their places due to pollution.

Hope Central Asian countries would give more importance to restoring Aral Sea to its original form.

Read Full Post »

%d bloggers like this: